The view enabled_roles identifies the
currently "enabled roles". The enabled
roles are recursively defined as the current user together with
all roles that have been granted to the enabled roles with
automatic inheritance. In other words, these are all roles that
the current user has direct or indirect, automatically inheriting
membership in.

For permission checking, the set of "applicable roles" is applied, which can be
broader than the set of enabled roles. So generally, it is better
to use the view applicable_roles instead
of this one; see also there.